Problem: Christopher has lunch at a restaurant and the cost of his meal is $\$35.00$. He would like to leave a $10\%$ tip. What is his total bill including tip?
The tip amount is equal to $10\% \times \$35.00$ To calculate a $10\%$ tip, move the decimal point in $\$35.00$ one place to the left. $10\%$ $\times \$35.00$ $\$3.50$ The cost of the meal plus the amount of the tip will equal the total bill amount. $\$35.00 + \$3.50 = $ $\$38.50$ The total cost of the bill is $\$38.50$.